As computer memory has continued to expand, more and more documents are being stored electronically (e.g., on computers), typically in file management systems. Electronically stored versions of documents offer the benefits of remote access, easy editing, and status monitoring.
Despite the increased use of electronically stored versions of documents, however, hard copy versions (e.g., paper) also continue to be used extensively. Paper versions offer the benefits of reduced eye strain while reading, easier verifiability, satisfying legal requirements, and user access even in non-computer friendly environments.
Because documents may exist in non-physical versions and hard-copy versions, it is often difficult to know which version of a document is the most current. Also, it is difficult to know which version is valid.